Chuck



Dec. 12, 1933. w M SNYDER 1,939,147

CHUCK Filed June 18 1950 Mlm @M @ya Patented Dec. 172, 1933 1,939,

UNITED STATES PATENT OFFICE CHUCK Walter M. Snyder, Detroit,V Mich., assignor to Sundstrand Machine Tool Co., Rockford, Ill., a. corporation of Illinois Application June 18, 1930. Serial No. 461,913

15 claims. (ol. 82.4.0)

The invention relates generally to chucks elOSing fOICeiS releaSed land the Weight f the adapted for use in machinetools such as lathes WOIk iS released flOIn the Centersand it relates more particularly `to chucks where- The abOVe and Other ObJ'eCtS are Obtained in in the retarding action of the tools on the work the preferred embodiment of the invention illusis utilized to clamp the chuck jaws firmly onto trated herein through the provision 0f a chuck oo the work piece. having a plurality of radially movable jaws each Chucks of this character heretofore have emhaving a Tack theIeOn engaged by piniOnS m0111117- ployed a plurality of toothed eccentrics pivotally ed 0n the Chuck bOCly, and a Ting gear engaging mounted in circumferentially spaced relation all of the pinions and having alug projecting about the chuck axis and arranged to engage the longitudinally from the Chuck bOdy Wneieby the 66 Work with increasing force as the rotation of the Ying geef muy be moved by a dog Seeuied 0n a work by the chuck is resisted by the tools. Such Werk Piece and arranged i50 engage the lng When chucks are objectionable since the action of each the rotation of the work pieceis retarded so as jaw is independent of the other jaws with the t0 clamp the jaws simultaneously upon the work result that the Work may be shifted transversely Dieee- 70 in the4 chuckv after the Cutting operation has Other objects and advantages will become apstarted. parent from the following detailed description The primary object of the present inventionteken in COmieCtOn With the aeeompanying is to provide a new andimprovedchuck of this drawing, in Whieh 10 character having jaws movable toward and away Figk 1 is en end eieV-'itiouei VieW 0f a Chuck 75 from the Work by a Common operating means embodying the invention in its preferred form, arranged to cause simultaneousmove'ment of all Certain 0f the parte bei-'ug breken Way t0 ShOW of the jaws, together with means having a single the enclosed jaw-Operating mechanismnon-rotative connection with the work and act- Fig- 2 iS a Seetiouai VieW 0f the Chuck taken' ing on the operating means to cause simultaneous along the line 2-2 0f Fig- 1- clamping of the jaws when rotative movement Fig- 3 ShOWS diagfammatieally the manuel 0f of the work by the chuck is retarded, as for inmounting Such eq Chuck in a doubie end lathe stance, by application of the tools to the work. Fig 4 is a Somewhat diagrammatic end eleva- Another objeol; is to provide Snell o ohuok tional view of the .chuck taken from the line wherein the jaws are simultaneously actuated by 4 4 v0f Fig. 3 Showing a work piece in operative 35 means adapted to be operated by an abutment or relation. t0 the Chuekdog on the work whereby to cause the work to be F01 Purposes 0f 'disclosure the Preferredforni clamped with a, force proportional to the resist of the invention is illustrated in the drawing and ance impressed upon the work by the tools' will hereinafter be described in detail as a cen- When a chuck s'used, for driving the work ter drive chuck for a double end lathe, but it 9o al; or near the oenterln a double end lathe the is to be understood that this disclosure is not jaws must be retracted for a considrable ds intended as a limitation of the invention to the tance in order to facilitate the endwise insertion pari-'miller form Shown 1t being contemplated of the work pieces through the opening in the that Venous Changes, might be mede by those 4 chuck, and another objectI of the invention is to Skilled im the art Wlthqut departmgfrom the 95 provide an automatically operable chuck having Spnlt and Scope of the Inventum as defined by jaws which may be readily and quickly retracted the appended clalms' t .dp 1 th 1 th h k In the preferred form herein illustrated the ino prow a erge Openmg rougi e c C vention is embodied in a chuck 10 adapted for When the laws of a chuck are retracted for use as a center drive chuck in a double end lathe loo a Conslderable dlstan as m a Gente? dmv@ having a head-stock center 1l and alongitudinalchuck the manual performance 0f the Jaw re' ly adjustable tailstock center 12 both mounted tracting movement requires considerable time, on o bed 13 and adopted to rotatably supportian and another Object 0f the inVentiOn iS'tO DIO- elongated work piece 14 for a performance of a vide a chuck for such -lathes wherein the jaw plurality 0f turning and facing operations by 105 operating means comprises reversible gearing means of a plurality of tools 15 shown diagramcapable ofv being moved by force applied Vto matically in Figs. 3 and 4. either end of the gearing so that the weight of As shown in Figs. l and 2, the chuck comprises the work in the chuck jawswill cause the -jaws a main body16 rotatably mounted on the bed to move toV their open position vwhenthe jaw 13 coaxially with the centers 11 and 12 by means 110 of a ball bearing 17 carried on a frame 18 fixed on the bed. In the present case the chuck is driven from a suitable power source through a pinion 19 which engages a gear 20 fixed on one side of the body 16.

When the chuck is intended for use on a double end lathe, as in the present case, the body 16 has a central aperture 21 formed therein through which the elongated work piece 14 may be passed for the purpose of supporting it between the two centers l1 and 12. Opening into the aperture 21 are a plurality of radial bores 22, formed in the body 16 and disposed in circumferentially spaced relation about the rotative axis of the chuck to provide slideways for a plurality of work engaging jaws 23, one of which is mounted in each of the bores 22. Each of the jaws 23 is preferably held against rotation and its longitudinal movement limited by a screw 24 (Figs. 1 and 2) extending into the chuck body and engaging a longitudinal slot 25 formed in one side of the jaw 23.

In accordance with the present invention the jaws 23 are moved in unison toward and away from the rotative axis of the chuck whereby to clamp the work, and the means for accomplishing this result is preferably of such a character that movement may be transmitted with equal facility from the operating means to the jaws and vice versa, since by providing such a reversible power transmitting connection the unclamping of the work may be greatly facilitated. y

To this end a rack 26 is formed on each of the jaws 23 within the chuck body 16 and a pluralityv of pinions 27 are rotatably mounted on the body,

j one adjacent to each of the jaws and in engagement with the racks 26. The pinions 27 are rotatable about axes parallel to the chuck axis and are mounted in cylindrical chambers 28 formed in the chuck body. The chambers 28 each open x into an annular recess 29 formed in the body, in

which recess a ring gear 30 is mounted for rotative movement relative to the chuck body, and each of the pinions 27 extends axially of the chuck past the sides of the jaws and into engagement with the teeth of the ring gear 30. Thus, the jaws 23'may be moved in unison toward and away from a work piece-by relativerotative movement of the ring gear 30 and the chuck body.

In the performance of a turning or facing oper- Y ation upon the work piece 14, illustrated in Fig.

3, the chuck 10 is rotated in the direction indicated by the arrows in the drawing, and the jawoperating means is arranged to move the jaws 23 toward clamping position when the ring gear 30 ismoved relative to the chuck body in the opposite direction, that is, clockwise as` shown in Figs. l and 4. Such relative movement of the ring gear and the vchuck body may be obtained by retarding the movement of the ring gear 30 while the chuck is rotated in a counter-clockwise direction (Figs. 1 and 4), and such retardation of the ring gear 30 is preferably obtained by the action of the cutting tools 15 on'the work and is transmitted through the work to the ring gear.

When thework 14 does not have a peripheral abutment of any kind, as in the present case, the retarding action of the tools may be transmitted to the jaw operating means by means detachably secured to each piece of work. This means is preferably in the form of a dog 31 embodying means for effecting a quickly detachable connection with the work. For the purpose of attaching the dog 31 to the work, the dog has an enlarged end 32 having an angular aperture 33 through which the work 14 may extend. A locking pin 35 may be provided for securing the dog 31 to the work.

In its operative position on a piece of work, the dog 31 extends radially from the work to engage an abutment in the form of a lug 37 provided on the ring gear 30. The lug 37 projects longitudinally of the chuck through an arcuate slot 39 formed in a closure plate 40 which is secured to the surface of the chuck in closing relation to the annular recess 29.

When the chuck 10 is rotated and the tools are brought into engagementvwith the work to effect a cutting operation, the dog 31 on the work will be engaged by the lug 37 and will cause relative movement of the ring gear 30 and the chuck body to clamp the work in the chuck. The clamping force thus exerted upon the work will at all times be directly proportional to the force being exerted on the work by the tools.

means, the weight of the work will cause all of the jaws to be moved to their open or retractedv positions. The work piece 14 may then be withdrawn an another work piece easily inserted due to the large opening between the jaws which may be provided,

as a practical matter, by reason of the automaticopening and closing of the jaws. In practice a plurality of dogs 31 are provided Whichmay be secured to a number of diierent work pieces andf hence a new piece of work may be inserted into 'r the machine as soon as the finished work piece has been removed. Y

From the foregoing it will be apparent that the invention provides an improved chuck operable invariably to clamp the work with a force proportional to the resistance applied to the work by the cutting tool. By reason of the fact that the dog on the work has a direct rather than a wedging abutment with the jaw operating means,

the jaw clamping force is released as soon as the tools are withdrawn, thereby enabling the operator to remove the work without the performance of an unclamping operation. The re-` versible gearing employed in the chuck contributes to this result and makes possible theY provision of a chuck having a large opening so that the work may be inserted readily.

Iclaim as my invention:

1. A chuck comprising a body adaptedto be rotated about a given axis, a plurality of jaws mounted on saidbody in circumferentially spaced relation about said axis for radial movement toward and from said axis, means operableto move said jaws including a member movable circumferentially about said axis, and means on said memr ber? adapted to be connected'to a work piece to prevent relative rotation of the work andsaid means in one direction whereby to cause simultaneous clamping movement of all of said jaws when rotation of the work is retarded.

2. In a device of the class described, a chuck body adapted to Vbe rotatede about a given axis, means for rotating said body, a plurality of circumferentially spaced jaws mounted on saidbody for radial movement with respect to said axis means for actuating said jaws in unison including a `member movable circumferentially about said axis, and a dog adapted to be mounted on a Work piece to engage said member and clamp the jaws by rotation of thework piece relatively to the chuck.

, 3. The combination of a chuck having abody adapted for rotation about a given axis, a plurality of clamping jaws mounted on said body and movable'toward and away from a work piece positioned for rotation about said axis, means mounted on said body for moving said jaws including ,a part movable on said body, and a dog adapted to be fixed on a work piece in position to engage and move said part on said chuck during relative rotation of the work and said chuck in one direction to clamp said jaws on .the work. Y

4. In adevice of the character described the combinationzof a rotatable chuck body,.a `plurality of jaws mounted on said body for movement toward and. away from a work piece positioned for rotation about the rotative axis of the chuck body and arranged to engage and clamp a work piece at a plurality of circumferentially spaced points, means for moving said jaws including a part movable with respect to said chuck body and operatively connected` to all of the jaws, and means adapted to be mounted on a work piece to engage and move said part relatively to the chuck body when rotation of the work by the chuck is retarded.

5. The combination of a chuck having a rotatable body, means for rotating said body, Work centering and clamping members movable toward and away from a work piece, operating means for moving said members in unison to clamp a work piece in the chuck, said operating means including a part movable relatively to said body circumferentially of said axis, and means acting between the work pieceand said part as an incident to the application of a cutting tool to the work during rotation of said chuck to move said part relatively to said body to clamp said members on the work.

6. A work driving chuck comprising, in combination, a chuck body rotatable with the work, circumferentially spaced work clamping and driving jaws carried on said body and movable toward and away from a work piece rotatable about the axis of said chuck body, a jaw operating member carried on said body and movable relatively thereto, and gearing between said member and all of said jaws arranged to transmit movement with equal facility from said member to the jaws or vice versa.

'7. A chuck comprising a rotatable chuck body,V

a plurality of jaws mounted on said body in circumferentially spaced relation for sliding movement radially toward and away from the chuck axis, adapted to engage a Work piece without wedging action, a member movably mounted on said body, and gearing between said member and all of said jaws arranged to transmit movement with equal facility from said member to said jaws or vice versa, said member projecting from the body so as to be engageable by a dog on the work when the chuck is rotated.

8. The combination of a rotatable chuck body Arotatable with the work, work clamping and driving jaws mounted in circumferentially spaced relation on said body for movement toward and from a portion of a work piece positioned for rotation about the rotative axis of the bodyy and arranged to engage a work piece without wedging action, a jaw actuating member mounted on said body for circumferential movement relatively thereto, gearing between said member and all of said jaws arranged to move said jaws and to transmit movement with equal facility from said 1 member to the jaws or vice versa, means for driving-said chuck body independent of said gearing, and means for retarding themovement of said jaw actuating `member relatively to the chuck body during rotation of said chuck to clamp said jaws on a work piece, said means automatically becoming ineiective to clamp said jaws when the chuck is stopped.

9. A work driving chuck comprising, in combination, a rotatable body rotatable with the work, a plurality of work clamping and driving jaws mounted in circumferentially spaced relationV on said body for movement toward and away from a work Vpiece positioned for rotation about the rotative axis'of the body, a plurality of pinions mounted in said body, one of said pinions being adjacent to each of said jaws, a rack on each of said ljaws engaging the adjacent pinion, a ring gear mounted on said body for rotation about the chuck axis and operatively connected to said pinions to rotate the same in unison, anda lug on said ring gear projecting'from said body for engagement by an actuating means.

l0. A work driving `chuck comprising, in combination, a rotatable chuck body rotatable with the I ble circumferentially of said body adapted to be engaged constantly during rotation of the chuck vjaws in unison, said means including a part movabody to retard movement of said part and apply a clamping force to the jaws, and means mounted independently of the chuck arranged to engage said part to apply a clamping force to the jaws.

` l1. The combination of a rotatable chuck body, driving mechanism for rotating said body in one direction, a plurality of jaws mounted on said body for movement relatively thereto into clamping engagement with a work piece positioned along the rotative axis of said body, means mounted on said body operable to move said jaws in unison, said means including a part movable circumferentially of said body, an abutment on said part facing in an advancing direction with relation to the direction of rotation imparted to said body by said driving mechanism, said jaw operating means being operable to clamp the work during rotation of said chuck by a restraining force applied to the advancing face of said abutment, and a dog adapted to be clamped on a work pieceto lie in the path of said abutment whereby said abutment rotates the work during the initial rotation of the chuck, said dog and said abutment cooperating, when the work is retarded by application of the tools thereto, to clamp said jaws upon the work in unison.

12. In a machine tool, the combination of a rotatable chuck body, a chuck jaw mounted on 1141 f said body for movement toward and away from a portion of a work piece positioned for rotation about the rotative-axis of the body, means for moving said jaw including a member mounted on said body and movable relatively to the body to move said jaw, and means arranged during rotation of the chuck to act between said member and a work piece in said chuck to transmit the retarding action of the tools from the work to said member to cause clamping movement of the jaw.

13. In a lathe having means forrotatably sup' porting a work piece, the combination of a driven chuck rotatable about the axis of said means, a plurality of jaws movably mounted in said' chuck, a member movably mounted in saidy chuck for rotation relatively thereto about. the rotative axis of the chuck, means connecting said member with said jaws operable to move said jaws simultaneously upon rotative movement of said member relatively tosaid chuck, a lug xed on said member and projecting longitudinally from said chuck, and a dog. adapted to benxed on a work piece carrier by said work supporting means and engageable with said lugv in the rotative movement of the chuck to` clamp said jaws on the work piece. Y

14. A work driving chuck comprising a chuck body adapted to be rotated about a lgivenaxis, a plurality of `work clamping and driving jaws mounted in'ciroumferentially spacedrelation on said body for straight line movement radially toward and away from said axis, a plurality of pinons mounted inv said body for-rotation on axes parallel to the chuck axis, one of .saidpinions being adjacent to eachof said jaws, a rack on eachl of saidjaws engaging the adjacent pinion, said pinions extending parallel to said chuck axis beyond said jaws, a gear mounted in said body and engaging the projecting ends of said pinions, said ring gear being freely rotatable relatively to said body, and means operable only during rotation of the chuck for retarding the movement oil the ring gear relatively to the body so as to move the chuck jaws toward said axis.

15. A work driving chuck comprising a rotatable chuck body, a plurality of work clamping and driving jaws mounted on said body for rotation therewith and in circuinferentially spaced relation for movement toward and away from a workpiecepositioned for rotation about the chuck axis, each of said jaws having a rack formed thereon, a plurality of pinions mounted in said body, one engaging each one of said racks, a gear mounted on said body and operatively connectedl to each of said. pinions to rotate the same, and

means operable to rotate said gear to move said jaws toward said axis and maintain a clampingI action of the jaws on a work piece during rotation of the chuck,V said means being ineffective to maintain said clamping action when the chuck is stopped.

- WALTER M. SNYDER. 

